ReactionTests vs MJJ Tools

A side-by-side comparison built from both listings. Blank cells mean the company has not given that detail; we never guess.

ReactionTests compared with MJJ Tools
Detail	ReactionTests	MJJ Tools
What it does	Test your visual reaction time for free	160+ free online tools and utilities for calculations, conversions, and productivity
Stage	Not given	Startup
Founded	Not given	2024
Based in	Not given	Not given
Pricing model	Free	Not given
Pricing	Not given	Not given
Key features	Five-round visual reaction test with millisecond timing Seven-round sound reaction time test Local result history with up to 300 sessions stored Consistency measurement showing standard deviation of scores Download score card as image Sound calibration for personal offset adjustment Reference data from published research studies	160+ free online tools
What makes it different	No account or login required to use the test Results stored locally in browser for privacy Compare full sessions to understand consistency, not just fastest round Research-backed reference data from laboratory studies	Instant access without downloads, installations, or registration required
Free plan	Not given	Not given
Open source	Not given	Not given
Platforms	Not given	Not given
Public API	Not given	Not given
Community votes	0	0
DR (Domain Rating by Ahrefs)	3 no change since last check	9 no change since last check
Trust Flow (Majestic)	0	0
Citation Flow (Majestic)	11	21
Referring domains (Majestic)	1	11

3 details filled in for both companies.